1. Field of the Invention
This invention relates to the field of crossover systems for use in audio amplifier systems. In particular, it relates to crossover networks that provide separate frequency responses suited to the different auditory sensitivity characteristics of male and female listeners.
2. The Prior Art The use of audio amplifiers with output circuits having multi-range crossover networks to supply different parts of a total band of frequencies to different loudspeakers, each designed to handle the part of the spectrum of frequencies directed to it, is well known. Illustrative examples of such networks are to be found in the following U.S. patents:
______________________________________ U.S. Pat. No. Issued Inventor ______________________________________ 3,838,215 Sep. 24, 1974 Haynes, Jr. 4,237,340 Dec. 2, 1980 Klipsch 4,282,402 Aug. 4, 1981 Liontonia 4,593,405 Jun. 3, 1986 Frye et al. 4,606,071 Aug. 12, 1986 White, Jr. 4,771,466 Sep. 13, 1988 Modaferri 5,129,006 Jul. 7, 1992 Hill et al. ______________________________________
Frye et al. and White Jr. disclose loudspeaker systems in which there are crossover circuits for separating audio signals into two bands: an upper band to drive a tweeter and a lower band to drive a woofer. Haynes, Jr., Klipsch, Liontonia, Modaferri, and Hill et al. disclose systems with crossover networks arranged to separate the audible range of frequencies into three bands, the middle band being used to drive a third speaker.
The crossover networks in all of these patents provide different filtering characteristics and the networks are suitable for operation in stereo systems in which the sounds reproduced by speaker systems on the listener's left are different from those reproduced by speaker systems on the listener's right at any given instant. However, there is no suggestion of providing two sets of crossover networks having different frequency response characteristics based on physiological differences in the auditory response of male and female listeners. In the case of existing stereophonic systems, the crossover networks controlling signals to speaker systems on the left will be the same as the crossover networks controlling signals to speaker systems on the right.
Quadraphonic speaker systems have also been produced in which there are speakers on the left and right in front of a listener and on the left and right behind the listener. In such systems, it is common to attenuate the higher frequency components of audio signals supplied to speakers behind the listeners in comparison with those same components of the same audio signals supplied to speakers in front of the listeners. As in the case of stereophonic systems, the quadraphonic signals are not further modified to accommodate physiological differences in male and female listeners.
I have found that women prefer that the sounds reproduced by a speaker system be accentuated in the higher part of the audible range and attenuated in the lower part relative to sounds in the middle range of frequencies between those in the higher and lower parts of the audible range, and that men have just the reverse preference.